Falls among the elderly, one of the most common reasons requiring medical intervention and a contributing factor in 40% of nursing home admissions, are a major health problem. Several studies have identified quantifiable gait markers that appear to distinguish between elderly "fallers" and non-fallers. These studies have relied on data acquired in gait-laboratories. Extending gait assessment capability, and falls detection, into the home could provide valuable before-the-fact information on gait weakness evolution, which in turn could be used to assess the efficiency of counter measures. Current mobile gait analysis techniques are insufficient because they rely on compliance or are too intrusive. The development of a new gait assessment and falls monitor is proposed. The device is passive and obtains gait data from sensing floor vibrations as well as a minimally invasive wireless device, precluding the need to walk on special surfaces or be observed by cameras. This study's principal aim is to validate the device's performance through a comparison with accepted gait assessment techniques at the Physical Medicine and Rehabilitation Gait lab at the University of Virginia Health System PUBLIC HEALTH RELEVANCE: An estimated 20% - 40% of community-dwelling elderly fall at least once a year 2 and this rate increases for nursing home residents. Fall-related injuries are among the most common reasons requiring medical intervention and are a contributing factor in 40% of nursing home admissions. The cost of falls to the national economy is significant. In 1994 the total cost due to falls was estimated to be $20.2 billion. This number is expected to climb to $32.2 billion by 2020. One suggestion for reducing the number of falls has been the creation of a fall risk assessment for institutional residents, an important component of which is gait assessment. In view of the results obtained during the Phase I effort, it appears that the floor sensor system may be able to answer a well defined need for which there is presently no other solution that promises to be as readily implementable and for which the market potential is significant.